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Groups > comp.lang.forth > #52272
| From | anton@mips.complang.tuwien.ac.at (Anton Ertl) |
|---|---|
| Newsgroups | comp.lang.forth |
| Subject | Re: 1 /STRING vs SNIP |
| Date | 2016-10-28 16:50 +0000 |
| Organization | Institut fuer Computersprachen, Technische Universitaet Wien |
| Message-ID | <2016Oct28.185046@mips.complang.tuwien.ac.at> (permalink) |
| References | (1 earlier) <2016Oct19.095231@mips.complang.tuwien.ac.at> <b8b685f8-7365-4dfa-b632-2764bf46932f@googlegroups.com> <2016Oct27.114220@mips.complang.tuwien.ac.at> <5812fe2f.243659084@news.eternal-september.org> <f909012d-bdb9-40ee-856a-ab30f60ed83e@googlegroups.com> |
jasmijn Bonting <tessa.bonting@gmail.com> writes:
>Op vrijdag 28 oktober 2016 09:31:47 UTC+2 schreef Stephen Pelc:
>> On Thu, 27 Oct 2016 09:42:20 GMT, anton@mips.complang.tuwien.ac.at
>> (Anton Ertl) wrote:
>>
>> >It can be reduced to two instructions on IA-32, as SwiftForth demonstrates:
>> >
>> >see foo2
>> >8083C4F 1 # 0 [EBP] ADD 83450001
>> >8083C53 1 # EBX SUB 83EB01
>> >8083C56 RET C3 ok
>> >
>> >Apparently SwiftForth has an optimization rule for n /STRING; whether
>> >this is faster than the VFX code depends on the actual processor.
>>
>> At some stage in the past (I forget for which x86 CPU),
>> memory/immediate instructions became very slow. At that point,
>> we removed their use by the VFX code generator. Ho, hum, time
>> to read up on current CPUs.
>>
>> Stephen
>>
>
>It is still slow, since the total instruction for large immidates is longer then 7 bytes and has to pre decoded before the next instruction.
>The instruction by itself is a 4 micro cycle instruction and can not
>combined with a other non 1 micro opcode instruction.
I have now done a benchmark: ten copies of the "1 /STRING" code, but
with different memory locations for the second stack items to avoid
the dependence-through-memory slowdown that would probably swamp all
other effects. Here are two copies:
VFX-like SF-like
movq (%rdi), %rax addq $1, 0(%rdi)
addq $1, %rax subq $1, %rsi
movq %rax, (%rdi) addq $1, 8(%rdi)
subq $1, %rsi subq $1, %rsi
movq 8(%rdi), %rax
addq $1, %rax
movq %rax, 8(%rdi)
subq $1, %rsi
100M iterations of these ten copies take the following number of cycles:
VFX-like SF-like
1537853028 1167890963 Phenom II X2 560
1105969806 1021509951 Core i7 4690K (Haswell)
So the SwiftForth-like code is faster than the VFX-like code on both
the Phenom II and the Haswell.
- anton
--
M. Anton Ertl http://www.complang.tuwien.ac.at/anton/home.html
comp.lang.forth FAQs: http://www.complang.tuwien.ac.at/forth/faq/toc.html
New standard: http://www.forth200x.org/forth200x.html
EuroForth 2016: http://www.euroforth.org/ef16/
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1 /STRING vs SNIP foxaudioresearch@gmail.com - 2016-10-18 19:31 -0700
Re: 1 /STRING vs SNIP Ron Aaron <rambamist@gmail.com> - 2016-10-19 07:24 +0300
Re: 1 /STRING vs SNIP anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-10-19 07:52 +0000
Re: 1 /STRING vs SNIP hughaguilar96@gmail.com - 2016-10-19 16:58 -0700
Re: 1 /STRING vs SNIP "HAA" <someone@microsoft.com> - 2016-10-21 16:01 +1000
Re: 1 /STRING vs SNIP hughaguilar96@gmail.com - 2016-10-21 00:51 -0700
Re: 1 /STRING vs SNIP hughaguilar96@gmail.com - 2016-10-21 00:57 -0700
Re: 1 /STRING vs SNIP trans <transfire@gmail.com> - 2016-10-21 05:20 -0700
Re: 1 /STRING vs SNIP "HAA" <someone@microsoft.com> - 2016-10-22 00:25 +1000
Re: 1 /STRING vs SNIP trans <transfire@gmail.com> - 2016-10-21 09:13 -0700
Re: 1 /STRING vs SNIP anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-10-21 16:24 +0000
Re: 1 /STRING vs SNIP albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2016-10-21 20:06 +0200
Re: 1 /STRING vs SNIP trans <transfire@gmail.com> - 2016-10-21 14:19 -0700
Re: 1 /STRING vs SNIP "HAA" <someone@microsoft.com> - 2016-10-22 13:46 +1000
Re: 1 /STRING vs SNIP stephen@mpeforth.com (Stephen Pelc) - 2016-10-22 11:34 +0000
Re: 1 /STRING vs SNIP anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-10-22 13:49 +0000
Re: 1 /STRING vs SNIP "HAA" <someone@microsoft.com> - 2016-10-24 11:15 +1000
Re: 1 /STRING vs SNIP albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2016-10-24 03:01 +0200
Re: 1 /STRING vs SNIP "HAA" <someone@microsoft.com> - 2016-10-24 13:29 +1000
Re: 1 /STRING vs SNIP anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-10-24 11:15 +0000
Re: 1 /STRING vs SNIP hughaguilar96@gmail.com - 2016-10-24 19:44 -0700
Re: 1 /STRING vs SNIP "HAA" <someone@microsoft.com> - 2016-10-29 11:17 +1000
Re: 1 /STRING vs SNIP Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-10-29 04:09 -0500
Re: 1 /STRING vs SNIP anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-10-29 16:44 +0000
Re: 1 /STRING vs SNIP hughaguilar96@gmail.com - 2016-10-29 17:11 -0700
Re: 1 /STRING vs SNIP "HAA" <someone@microsoft.com> - 2016-10-31 19:11 +1100
Re: 1 /STRING vs SNIP anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-10-31 08:47 +0000
Re: 1 /STRING vs SNIP trans <transfire@gmail.com> - 2016-10-21 03:49 -0700
Re: 1 /STRING vs SNIP hughaguilar96@gmail.com - 2016-10-22 20:02 -0700
Re: 1 /STRING vs SNIP hughaguilar96@gmail.com - 2016-10-22 20:13 -0700
Re: 1 /STRING vs SNIP trans <transfire@gmail.com> - 2016-10-22 21:09 -0700
Re: 1 /STRING vs SNIP hughaguilar96@gmail.com - 2016-10-23 18:36 -0700
Re: 1 /STRING vs SNIP alex <alex@rivadpm.com> - 2016-10-27 14:07 +0100
Re: 1 /STRING vs SNIP hughaguilar96@gmail.com - 2016-10-27 19:12 -0700
Re: 1 /STRING vs SNIP alex <alex@rivadpm.com> - 2016-10-28 19:39 +0100
Re: 1 /STRING vs SNIP hughaguilar96@gmail.com - 2016-10-28 20:26 -0700
Re: 1 /STRING vs SNIP foxaudioresearch@gmail.com - 2016-10-26 19:52 -0700
Re: 1 /STRING vs SNIP anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-10-27 09:42 +0000
Re: 1 /STRING vs SNIP foxaudioresearch@gmail.com - 2016-10-27 06:46 -0700
Re: 1 /STRING vs SNIP stephen@mpeforth.com (Stephen Pelc) - 2016-10-28 07:31 +0000
Re: 1 /STRING vs SNIP jim <anon@example.com> - 2016-10-28 11:33 +0100
Re: 1 /STRING vs SNIP jasmijn Bonting <tessa.bonting@gmail.com> - 2016-10-28 04:09 -0700
Re: 1 /STRING vs SNIP stephen@mpeforth.com (Stephen Pelc) - 2016-10-28 12:41 +0000
Re: 1 /STRING vs SNIP anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-10-28 16:50 +0000
Re: 1 /STRING vs SNIP Chris Curl <ccurl609@gmail.com> - 2016-10-28 10:59 -0700
Re: 1 /STRING vs SNIP anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-10-29 10:17 +0000
Re: 1 /STRING vs SNIP "HAA" <someone@microsoft.com> - 2016-10-19 20:19 +1000
Re: 1 /STRING vs SNIP foxaudioresearch@gmail.com - 2016-10-19 05:12 -0700
1 /STRING vs SNIP trans <transfire@gmail.com> - 2016-10-21 04:07 -0700
Re: 1 /STRING vs SNIP albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2016-10-21 15:50 +0200
Re: 1 /STRING vs SNIP hughaguilar96@gmail.com - 2016-10-25 16:38 -0700
Re: 1 /STRING vs SNIP "David N. Williams" <williams@umich.edu> - 2016-10-26 10:50 -0400
Re: 1 /STRING vs SNIP "David N. Williams" <williams@umich.edu> - 2016-10-26 10:53 -0400
Re: 1 /STRING vs SNIP albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2016-10-26 17:33 +0200
Re: 1 /STRING vs SNIP "David N. Williams" <williams@umich.edu> - 2016-10-27 10:16 -0400
Re: 1 /STRING vs SNIP Doug Hoffman <glidedog@gmail.com> - 2016-10-27 17:01 -0400
Re: 1 /STRING vs SNIP Coos Haak <htrofhc@gmail.com> - 2016-10-27 17:00 +0200
Re: 1 /STRING vs SNIP Hans Bezemer <the.beez.speaks@gmail.com> - 2016-10-22 12:25 +0200
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